1. Solutions!

2. I. What is a Solution?
A solution is a type of homogeneous mixture formed when one substance dissolves in another.
It is evenly mixed and does not settle out.
Can’t see the different particles.
Solutions can be mixtures of solids, liquids, or gases!

3. II. What Makes Up a Solution?
A solUte is the substance that is being dissolved.
i. It is usually in the SMALLER amount
ii. It is what YOU put in
A solvent is the substance that does the dissolving.
i. It is usually in the LARGER amount
c. The Universal Solvent is
water.

5. Examples
Solvent
Solution
Solute

7. III. Concentration
Concentration refers to how many solute molecules are present in a solvent.
It is how much “stuff” (solute) is in a place.
We use descriptive words to identify concentrations of solutions:
DiLute
(A Little amount of solute)
Concentrated
(A lot of solute)

8. (saturated)
(unsaturated)
Key:
Solute particles

9. IV. Dilute Solution
Dilute Solution: solution containing a small amount of solute compared with the amount of solvent present
Ex: Putting a drop of chocolate syrup in your tall glass of milk.
(When mom makes chocolate milk)

10. V. Concentrated Solution
Concentrated Solution: solution containing a large amount of solute compared with the amount of solvent present
i. Ex: When YOU make Chocolate milk!

12. VI. What is Solubility? What does that mean...?
Solubility is the ability of one substance to dissolve in another at a given temperature and pressure.
What does that mean...?
b. Solubility is how much “stuff” (solute) something hold at a specific temperature.

13. VII. How Can We Increase Solubility?
Increase the temperature
i. The hotter the temperature, the faster the molecules move so there is more space for more solute.

14. Increase the surface area
Solvent can hold more small pieces than large pieces.
Ex: crush sugar cubes
smaller surface area
(harder to spread out)
Larger surface area
(easier to spread out)

15. Increase the volume of solvent
i. The more solvent there is, the more solute it can hold.
ii. Ex: Adding more water. A pitcher of water(solvent) can hold more iced tea powder (solute) than a cup of water.

16. VIII. Ways to Chang the Dissolving Rate
a. Dissolving Rate -how quickly or slowly the solute dissolves.
b. Increase dissolving rate = it dissolves faster
c. Decrease dissolving rate = it dissolves slower
d. Ways to Increase the Dissolving Rate:
1. Change surface area (amount of space a material
takes up)
i. increase surface area = increase dissolving rate
ii. Decrease surface area=decrease dissolving rate.

17. 2. Stirring i. Increase stirring= dissolves faster ii
2. Stirring i. Increase stirring= dissolves faster ii. Decrease stirring = dissolves slower 3. Temperature: Changes not only the amount of the solute that can dissolve but changes how quickly it will dissolve! i. Increase temp=increase dissolving rate ii. Decrease temp=decrease dissolving rate

18. Pressure: Which is why a soda bottle emits gas when you open it – you decrease the pressure so it can’t hold as much
(Increase pressure=dissolves faster)

19. IX. Remember….
Temperature will affect how much solute is dissolved in a solvent; how much it CAN hold.
These terms are DESCRIPTIVE, and are used to COMPARE the amount of the solute compared to the solvent!

20. XIII. Remember Kinetic Energy?
As we increase the temperature of something, its molecules move faster, which will give more places for a substance to “hide” in a solution.
So the warmer the temperature, the more solute a solvent can hold!
Hot stuff can hold more than cold; think of hot tea vs. iced tea!

21. 4 Classes of Matter 3. ELEMENTS (pure substance): 1. MIXTURES
Fe, S, O, H, N
1. MIXTURES
4. COMPOUNDS (pure substance):
H2O, SiO2, CuSO4
Homogeneous
Heterogeneous
2. SOLUTIONS
Colloids
Can be decomposed by chemical changes:
H2O H + O
Mixtures can be separated by physical changes.